The present invention stems from a need to separate foreign objects from a mass of coins inserted into a machine, often by the public, in order to provide a total value of the coins. Such machines are increasingly being provided in public places, such as supermarkets to enable the public to dispose of their small change.
It should, however, be appreciated that the invention is not restricted to use in such self-service bulk coin counters but may have use in other coin-handling machines in situations where the coins inserted into the machine may have mixed with them foreign objects of various kinds.
In the absence of a separation device, the foreign objects are liable to jam the machine, or reduce the efficiency of the machine.
The foreign objects can be of various kinds such as fluff and all manner of items which are found in pockets and purses, such as pencils, buttons and pens, lipsticks etc, in short any item that can get picked up inadvertently with a batch of coins when the coins are loaded into a coin sorting/counting machine by a member of the public. In an industrial situation, such as a mint, contaminants of various kinds can arise, such as maize, shot and other abrasive and cleaning media.
Various types of coin cleaning devices for cleaning a mass of coins, prior to it being processed by a coin processing device, are known.
U.S. Pat. No. 5,482,916 discloses a coin conditioning device comprising a rotatable container, having perforated walls and vanes for causing the mass of coins to be conveyed forward through the container. The described coin conditioning device works like a screw tube conveyor, causing the mass of coins to tumble inside the conveyor, while non-coin matter is allowed to fall out of the container through the perforations in the walls.
WO 96/30877 discloses a similar, rotatable coin cleaning device, wherein the vanes are replaced by a screw conveyor that is arranged inside the perforated container.
The present invention stems from some work to provide a coin cleaning device which is fast and which provides an even flow of coins to the components downstream of the coin cleaning device.